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    <title>Document</title>
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    <div id="app">
        <div v-bind:id="dataId|formatId">hellovue</div>
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    <script>
        var vm=new Vue({
            el:"#app",
            data:{
                dataId:"dfff1"
            },
            filters:{
                formatId(value){
                    console.log(value)
                    console.log(value.indexOf('d'))
                    console.log(value.charAt(1))
                    return value ? value.charAt(1)+value.indexOf('d'):''
                }
            }
        })
    </script>
</body>
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